Signup or Sign Up: write “sign up” (two words) for the action, like “I will sign up today.” Write “sign up” (hyphenated) or “signup” for the thing, like “the sign up page.” Use the hyphen in formal writing. AP style accepts only “sign-up.”
This looks like a tiny spelling choice. It is really about grammar. One form is a verb, and the other is a noun or adjective.
This guide settles signup or sign up with simple steps. Every section has a clear example. The advice follows dictionaries and style guides.
Quick Answer – Signup or Sign Up
Try this:
- Find the main action in your sentence.
- If it is an action, write two words: “sign up.”
- If it names a thing, write “sign up” (or “signup”).
Example: “Please sign up on the sign up page.” The first is the action. The second is the thing.
Meaning and Definition of Each Word
“Sign up” means to join or register. “Sign up” or “signup” names the act, the form, or the page. Signup or sign up is just action versus thing.
Sign Up
How to spot it:
- Look for someone doing something.
- Check if it means “join” or “register.”
- Write two words.
Example: “I want to sign up for the class.”
Merriam Webster lists “sign up” as a verb. It dates the first known use to 1875.
Signup
Quick method:
- Look for a noun, like a form or page.
- Put “the” or “your” before it.
- Join it as one word only if your brand style does that.
Example: “Your signup is complete.”
Grammarist treat “signup” as a valid noun and adjective. Dictionary.com lists it as a variant of “sign up.”
Sign Up (Hyphenated)
The hyphen joins two words into one idea. Merriam Webster uses this form for the noun and adjective. AP style and print writing use it too.
Do this:
- Find the noun or adjective.
- Put a hyphen between “sign” and “up.”
- Read the sentence aloud.
Example: “The sign up sheet is on the desk.” Here, “sign up” is an adjective. For formal writing, this is the safe choice.
Key Differences Between the Words
The difference between signup or sign up is the job the word does. Ask what the word does in your sentence.
- “Sign up” is a verb (an action).
- “Sign-up” is a noun or adjective (a thing).
- “Signup” is an accepted one word variant, common in tech copy.
Example: “I will sign up after I fill in the sign up form.”
Signups or Sign Ups: Which Spelling Is Correct?
Both plurals are fine. Only the noun takes an “s” at the end.
Check it:
- Make sure the word is a noun.
- Add “s” to the end of the whole word.
- Keep the same style all through your text.
Example: “Sign ups doubled this month.” Or: “Signups doubled this month.” Pick one and stay with it.
Comparison Table
| Form | Part of Speech | Example |
| Sign up | Verb | “Sign up today.” |
| Sign up | Noun / Adjective | “The sign up sheet is full.” |
| Signup | Noun / Adjective (accepted variant) | “The signup page loads fast.” |
How to use it:
- Decide the job of your word.
- Find that job on the table.
- Copy the matching form.
Example: “Start your sign-up” is a noun use. So the hyphen form is correct.
Verb Forms Table: Sign Up, Signed Up, Signing Up
| Tense | Form | Example |
| Base | sign up | “I sign up every year.” |
| Third person | signs up | “Tom signs up early.” |
| Past | signed up | “She signed up yesterday.” |
| Present participle | signing up | “He is signing up now.” |
Quick method:
- Choose the tense.
- Change only the word “sign.”
- Keep “up” as a separate word.
Example: Write “signed up.” Never write “sign uped.”
Examples in Sentences
Real sentences make the rule easy.
Using Sign Up (Verb)
- Put a person before it.
- Add “for” if you need it.
- Check that it shows an action.
Example: “Over 100 students sign up for the camp each year.”
Using Sign Up or Signup (Noun/Adjective)
- Put “the” or “your” before it.
- Check that it names a thing.
- Re read for flow.
Example: “The sign up form has three fields.”
Signup or Sign Up Gmail
Opening a new email account is an action. So the verb form fits.
How to check:
- Ask, “What am I doing?”
- Creating an account is an action.
- Write “sign up for Gmail.”
Example: “I will sign up for Gmail today.” But: “The Gmail sign up page is simple.” Some sites use “Create account” to skip the debate.
Signup or Sign Up Online
Do this:
- Decide if you mean the action or the page.
- Action: “sign up online.”
- Page or form: “online sign-up.”
Example: “You can sign up online.” And: “The online sign up takes two minutes.” The rule stays the same on the web.
SignUpGenius: Brand Names Keep Their Spelling
SignUpGenius is a brand name. A brand keeps its own spelling.
Try this:
- Check if you mean the brand.
- Write it as shown: SignUpGenius.
- Use normal grammar for the other words.
Example: “We used SignUpGenius to sign up volunteers.”
Signup vs Sign In vs Log In
These three look alike. They do different jobs. UX Movement advises pairing “sign up” with “log in,” because “sign up” and “sign in” are easy to mix up.
Quick method:
- New user? Say “sign up.”
- Returning user? Say “log in” (verb) or “sign in.”
- For page names, use the noun “login.”
Example: “New here? Sign up. Already a member? Log in.”
Signup Button or Sign Up Button?
A button starts an action, so the verb form fits. Google’s web.dev sign up form guide uses a “Sign up” button. A CSS Tricks writer also prefers active verb phrases like “Sign Up” and “Log In.”
Do this:
- Ask, “Does this button start an action?”
- If yes, use “Sign Up.”
- Use the same label on every page.
Example: A button that reads “Sign Up” opens the sign-up page.
Common Mistakes
Spot it fast:
- Find the verb in your sentence.
- Split it into two words.
- Check the past tense.
Mistakes to avoid:
- “I will sign up.” Write “I will sign up.”
- “She sign uped.” Write “She signed up.”
- Mixing styles on the same page.
Example: “He signed up on the sign-up page.”
Tips to Remember the Difference
The “I” test settles signup or sign up in seconds.
- Try the “I” test. If “I __” works, use two words.
- Try the “the” test. If “the __” works, join it or add a hyphen.
- Practice with three sentences a day.
Example: “I sign up.” And: “The sign-up.” Remember: after “I,” split it. After “the,” join it.
Is Sign Up Hyphenated?
The verb never takes a hyphen. Only the noun and adjective do, in formal and AP style.
Check it:
- Find the part of speech.
- Verbs? No hyphen.
- Noun or adjective? Add the hyphen.
Example: “I sign up.” And: “The sign-up list.”
When to Use Each Word
The right choice in signup or sign up depends on your audience.
- “Sign up” for actions.
- “Sign up” for formal, news and AP-style writing.
- “Signup” for tech and brand copy, if your style guide allows it.
Do this:
- Know your audience.
- Pick one style guide.
- Use it everywhere.
Example: A news site writes “sign up page.” A software app may write “signup page.”
Grammar Rules: Phrasal Verb vs Noun
“Sign up” is a phrasal verb: a verb plus a small word. It stays split as a verb. As a noun, it is hyphenated or joined. WordPress core documentation uses the same rule: “sign up” for the verb, “sign up” or “signup” for the noun and adjective.
Follow the pattern:
- Spot the verb plus a small word.
- Keep it split as a verb.
- Hyphenate or join it as a noun.
Example: “Log in” (verb) becomes “login” (noun). “Sign up” becomes “sign up” or “signup.” That is the whole signup or sign up pattern.
Synonyms or Related Words
Related words: register, enroll, subscribe, join.
Try this:
- Pick a synonym that fits.
- Swap it into the sentence.
- Check that the meaning stays the same.
Example: “Sign up for the newsletter” means the same as “Subscribe to the newsletter.”
Signup Today or Sign Up Today
A call to action is a command. You tell the reader to act.
Quick method:
- Ask, “Is it a command?”
- If yes, write “Sign up today” or “Sign up here.”
- Use a one word label only when your brand style asks for it.
Example: “Sign up today and get free shipping.” And: “Sign up here to get updates.”
Signup Bonus or Sign Up Bonus
A bonus is a thing. So the word before it works as an adjective.
How to check:
- Find the noun “bonus.”
- The word before it describes it.
- Write “sign up bonus” or “signup bonus.”
Example: “Get a $50 sign up bonus.” Writing “sign up bonus” as two words is a common error.
Signup Sheet or Sign Up Sheet
Do this:
- Find the noun “sheet.”
- The word before it is an adjective.
- Write “sign up sheet” or “signup sheet.”
Example: “Add your name to the sign up sheet.” Writing Explained uses a similar case: a resume workshop with a sign up sheet in a student lounge.
AP Style: Sign Up or Sign Up
Writing Explained says AP style uses “sign up” for the verb and “sign up” for the noun and adjective. It does not accept the one word “signup.” Dictionaries are looser, so follow your own style guide.
Try this:
- Open your style guide.
- Verb: “sign up.”
- Noun or adjective: “sign-up.”
Example: “Sign up for the newsletter. The sign up form is below.”
Summary
- Verb: “sign up.”
- Noun or adjective: “sign up” (formal) or “signup” (tech).
- Pick one style and keep it.
Example: “Sign up now. Your sign up takes a minute.”
“Sign up” is what you do. “Sign up” is what you fill in. That is the whole signup or sign up rule.
Frequently Asked Questions
Is it signup or sign up?
“Sign up” is the verb. “Sign up” or “signup” is a noun or adjective.
Is “signup” a real word?
Yes. Grammarist and Dictionary.com accept it, but AP style prefers “sign-up.”
Is it sign up or signup?
Use “sign up” in formal, news and AP-style writing. Use “signup” only if your brand style allows it.
What is the past tense of sign up?
It is “signed up.” Never write “sign uped.”
Is it a sign up button or a sign up button?
Use “Sign Up” on buttons because a button starts an action.
Is sign up the same as log in?
No. Sign up creates a new account. Log in opens an existing one.
Conclusion
Signup or sign up is easy once you know each word’s job. Use “sign up” for the action. Use “sign up” or “signup” for the thing.
Pick one style and keep it. Run the “I” test when you doubt. Then fix any old pages that mix the forms.
